Wallpaper trimming and pasting machine



3 Sheets-Sheet 1 INVENToR Arn/wey fuman.

May 2, 1961 w. c. RENNE WALLPAPER TRIMMING AND PASTING MACHINE Filed Dec. 17, 1956 w. c RENNE WALLPAPER TRIMMING AND PAsTING MACHINE May 2, 1961 5 Sheets-Sheet 2 Filed Deo. 17, 1956 INVENTOR h//Y//m 6.' /Pe/// Y Wa. wim

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Filed DeC. 17, 1956 IIIJ United States Patent@ WALLPAPER TRIMMING AND PASTING MACHINE William C. Renne, 6115 Troost Ave., Kansas City, Mo.

Filed Dec. 17, 1956, Ser. No. 628,835

Claims. (Cl. 242-562) This invention relates to new and useful improvements in wallpaper trimming and pasting machines, and relates particularly to a machine of the type wherein the paper edges are trimmed, and paste is applied to the reverse side thereof, as the paper is drawn from a roll supported in the machine.

While machines of this general class have been devised heretofore, all of them within my knowledge have been successful at best only to a limited extent, due to the fact that they have not been capable of trimming the edges of the paper with sufficient accuracy, i.e. along suciently straight lines, to permit a workmanlike job of paperhanging, particularly the class of paperhanging known as butt-work. In this class of work the strips of paper are applied to the wall with their edges adjoining or abutting, not overlapping. Even very slight de-V viations from a straight line in trimming the paper will produce objectionable gaps between the paper edges, or equally objectionable intermittent overlapping of the edges.

yIn my opinion, the principal cause of the above defect has been improper support of the paper roll in the machine, in that said roll has heretofore been supported on some type of axle or spindle. In the first place, it is difficult if not practically impossible to center an axle or spindle accurately in the paper roll, since the roll is itself compressibly yieldable, and since said roll may be slightly crushed or ol-round so that the central opening therethrough is not perfectly cylindrical. In the second place, even if the roll be centered on an axle, the roll of paper has often been mashed or crushed in handling so that it is not cylindrical, and may be of varying cross-sectional contour from one end of the roll to the other. If either of the above conditions exist, the roll will wobble at least slightly as paper is drawn therefrom, and this wobble causes a periodic lateral movement of the paper as and after it leaves the roll. If this lateral movement reaches the trimming cutters of the machine, they will trim the paper edges in wavy or sinuous lines. In view of the fact that deviations from a straight line of as little as two-one thousandths of an inch, if occurring in a length of paper equal to or less than the circumference of the roll, will produce objectionable gapping in butt-work paperhanging, it will be seen that a high degree of accuracy is required.

Accordingly, the principal object of the present in vention is the provision of a wallpaper trimming and pasting machine of the general class described which will trim the paper with the degree of accuracy requisite to high quality butt-joint paperhanging. Generally, this object is accomplished by a centerless mounting of the paper roll in the machine. That is, the roll is held loosely against a guide member (preferably a pasteapplying roller) which is aligned laccurately with the trimming cutters. If the roll is out-of-round or irregular, the remainder of the roll may wobble or gyrate as required. Only the paper portion at and immediately following its point of departure from the roll is guided, and deformation of the roll hence does not affect the Pfenrea May 2, 1961r ICC path of the paper. Since it is desired that the guide member (paste roller) dominate the course of the paper, the paper is pressed thereagainst and contacts said roller over a substantial area, while such auxiliary guides and supports as are necessary to hold and support the paper roll against the paste roller are designed to affect the paper travel as little as possible.

Other objects are simplicity and economy of construction, eiciency and dependability of operation, and adapt ability to serve either as a paster or a trimmer, as Well as a combination paster and trimmer.

With these objects in view as well as other objects which will appear in the course of the specification,

reference will be had to the drawing, wherein:

Fig. l is a top plan view of a wallpaper trimming and pasting machine embodying the present invention, showing a roll of wallpaper positioned operatively therein,

Fig. 2 is a front elevational view of the machine as shown in Fig. l, with parts broken away,

Fig. 3 is an enlarged left end view of the machine as shown in Figs. 1 and 2,

Fig. 4 is an enlarged sectional view taken on lin IV-IV of Fig. l,

Fig. 5 is a slightly irregular-foreshortened sectional view taken on line V-V of Fig. 4,

Fig. 6 is a fragmentary, foreshortened sectional view taken on line VI-Vl of Fig. 4,

Fig. 7 is a fragmentary detached view of the paste spreader member,

Fig. 8 is an enlarged fragmentary sectional view taken on line VIII-VIII of Fig. 2,

Fig. 9 is an enlarged fragmentary sectional view taken on line IX-IX of Fig. 3, and

Fig. l0 is an enlarged sectional view of the paste or guide roller only, taken on line X-X of Fig. 5.

Like reference numerals apply to similar parts throughout the several views, and the numeral 2 applies to a tank adapted to contain liquid paste and having a bottom wall 4, front wall 6, rear wall 8, left end wall 10, and right end wall 12. As best shown in Fig. 4, front wall 6 is inclined upwardly and rearwardly and end walls 10 and 12 extend forwardly therefrom. Also at the forward edges thereof, each of end walls 10 and 12 is provided with an upward extension forming a stand-,

ard 1'4.

As best shown in. Fig. 5, a paste or guide roller axle 16 extends longitudinally and horizontally in tank 2, the

ends thereof being rotatably supported in a pair of bear? ing blocks 18 welded or otherwise xed respectively to the inner surfaces of end walls 10 and 12. The paste and guide roller 20 carried by axle 16, as best shown in Figs. 4, 5 and 10, comprises a hollow cylindrical body 22 disposed coaxially about axle 16, approximately midway between tank end walls 10 and 12. Said body member is provided with webs 24 spaced inwardly fromV the ends thereof, and provided centrally with bearing sleeves 26 journalled on axle 16. The roller is prevented from moving axially along the axle by a pair of collars 28 (Fig. 5) secured on the axle respectively at the distal sides of webs 24. Roller body 22 is -provided with a soft rubber facing 30 extending the full length thereof. The surface of said facing is preferably roughened, both to provide better traction against the paper roll 32 which rests against the roller as will be more fully described, and to render said roller more eflicient in elevating paste from tank 2 to the paper. y i

The paste roller 20 is provided at each end with` an adjustable extension 34, as best shown in Figs. 5 andY 10.

22, so as to be slidable into the open end portions of said body member 22. Each of the extension body members 36 is provided with a facing 40 of sheeps wool or the like. This facing normally has the same diameter as the main portion of the paste roller, but may be compressed to slide within main roller body 22. By moving extensions 34 inwardly or outwardly on axle 16, it will be evident that the effective length of the roller can be adjusted to the width of the paper roll 32. However, as shown in Fig. 5, the paste roller extensions are adjusted so as not to extend to the extreme edges of the paper. The edge portions of the paper to which paste is not applied will be trimmed olf later by the cutters to be described, and applying paste to the extreme edges of the paper might cause the paste to work around to the pattern side of the paper.

A pair of arms 42 and 44 are pivoted respectively to the upper ends of standards 14 of end walls 10 and 12 by means of screws 46, said screws being coaxial and parallel to axle 16. Said arms normally extend downwardly and rearwardly and have their rearward end portions resting respectively on the upper edges of end walls and 12. Each of said arms is provided adjacent its rearward end with an outwardly projecting pin 48 (see Figs. 3- and 5) which is engaged in a hole 50 formed in a leaf spring 52 affixed to the associated end wall 10 or 12 by rivets 54. Arms 42 and 44 are thus normally locked against movement, but may be pivotally raised after first flexing springs 52 outwardly to disengage them from pins 48.

Arms 42 and 44 are rigidly connected, adjacent pivot screws 46, by a cross bar 56 extending the full width of the machine and welded at its ends to said arms. Just below said cross bar, a hard surfaced cutter roller S8 is carried rotatably on an axis parallel to axle 16. Said cutter roller extends substantially the full width of the machine, being supported at each end by a screw 60 threaded in a boss 62 formed on the associated arm 42 or 44. Said screw extends inwardly and engages a ball bearing 64 (see Fig. 6) mounted in the end of roller 58, and said screw is prevented from turning accidentally by a lock nut 66 threaded therein and abutting boss 62. The cutter roller cooperates with a pair of cutting discs 68 which bear against said roller and function to trim the waste edge portions from paper 32 drawn forwardly from roll 32 and passing between roller 58 and discs 68, as will be more fully described.

Cross bar 56, which is disposed above the cutter roller, is provided along its forward edge with a depending wall 70 which extends closely adjacent the surface of roller 58, and is designed to prevent the entry of the loose end of paper between the roller and the bar. A paper cutting edge 72 is formed along the juncture between bar 56 and wall 70. Along its rearward edge, cross bar 56 carries :t depending wall 74 which extends substantially the full width of the machine and which is inclined downwardly and rearwardly, extending to a point spaced closely apart from the surface of paste roller 20, as best shown in Fig. 4.

Paper roll 32 rests against wall 74 as well as paste roller 20, and is urged loosely thereagainst by a plurality of at lingers 76, each of said fingers being pivoted by means of a bolt 7S to a slide 80 mounted on and movable along the upper edge of rear tank Wall 8. A coil spring 82 mounted on bolt 78 serves to urge the arm against paper roll 32. Each slide 80 also carries a forwardly projecting horizontal arm 84, which serves to prevent the paper roll from falling by accident into the paste tank. While three spring fingers 76 are shown, it will of course be understood that any number desired could be used.

The paper roll is held longitudinally in position by a pair of guides 86 and 88 disposed respectively at opposite ends thereof. Guide 86 is substantially rigid, constituting a metal plate in a plane at right angles to the axis of the roll and uverlapping the end of the roll, particularly that .4 portion of the roll at and adjacent the paste roller. Said plate is formed integrally with a slide 90 which is movable along the upper surface of cross bar 56, and which is adjustably secured to said cross bar by a screw 92 threaded in said cross bar and passing through an elongated slot 94 in the slide. Guide 88 constitutes a flexible leaf spring bearing resiliently against the end of roll 32 opposite guide 86, and attached as by screws 96 to a slide 98 similar to slide 90, slide 98 being secured to cross bar 56 by a screw 100 passing throughl an elongated slot 102 of the slide. Guides 86 and 88 serve to keep the paper roll positioned longitudinally in proper relation to the cutter discs 78, the distance between the guides being adjustable to rolls of different lengths by loosening screws 92 and 100. The rigidity of guide 86 constitutes it a xed index mark from which the positioning of the cutter discs may be measured. The longitudinal compressional load applied to the paper roll by spring guide S8 serves to slip the layers of paper in the roll over each other, longitudinally of the roll, in order that the edges of said layers will register precisely with each other, and shifting of the paper longitudinally of paste roller 20 will be prevented. This alignment of the layers could not occur if the roll is wound tightly, and a looser rewinding of some rolls will therefore be re# quired.

Paste from tank 2 which is applied to the lower (outer) surface of the paper by paste roller 20 is smoothed and evenly distributed over the paper by a spreader 104 disposed immediately below cutter roller 58 and extending the full length thereof. Said spreader constitutes a soft rubber blade having a serrated edge, as best shown in Fig. 7, and having its back edge, clamped in a metal channel 106. Said backing channel is provided at each end with a longitudinally extending threaded stub 108, said stubs extending outwardly respectively through bosses formed on tank end walls 1 0 and 12, and each having a lock nut 112 threaded on the extended end thereof; Said lock nuts may be loosened and channel 106 and stubs 103 rotated to vary the pressure of spreader blade 104 against the paper as it passes around cutter roller 58. Excess paste wiped from the paper by the spreader will drain back into the tank.

As best shown in Figs. 3, 4 and 9, each cutter disc 68 is mounted on an axle 114 mounted in a ball bearing 116 carried by a standard 118, said standard being attached rigidly to a slide 120. The slides 120 of the two cutter discs are slidably mounted respectively on a pair of carrier bars 122, each slide being securable on its carrier bar by a set screw 124. The two carrier bars are coaxial and disposed in end-to-end relation just forwardly of the upper edge of front tank wall 6, being parallel to cutter roller 58. Said bars each extend approximately one-half of the length of the tank. At their contiguous ends (see Figs. 2 and 8), the bars are each provided with a stub axle projection 126. both of said axles being carried for rotary and longitudinal sliding movement in a sleeve 128 afxed to the forward surface of wall 6. The contiguous ends of bars 122 are also connected, and urged toward each other, by a tension spring 130. The distal ends of bars 122 are each provided with a threaded stub axle projection 132 (see Fig. 2), said last named stub axles extending outwardly through holes provided therefor in tank end walls 10 and 12, and each having a knurled nut 134 threaded on the extended end thereof. By turning nuts 134, the position of cutter discs 68 transversely of the paper 32' may be very closely and accurately controlled.

At their contiguous ends, each of carrier bars 122 is provided with a downwardly extending crank 136 rigidly attached thereto, as best shown in Figs. l, 2, and 8. The free ends of said crank are confronting, and are spaced apart from each other. Said cranks engage and are urged forwardly whereby to urge cutter discs 68 against cutter roller 58. by a leaf spring 138 mounted on the forward face of tank wall 6. Said spring is generally flat, and -is `tiltableaboutfa -vertcal axis passing sub# stantially midway between the confronting ends of cranks 136. As best shown in Fig. 8, the spring is supported at its upper edge by a forwardly projecting lug 140 fixed to wall 6 and having a hemispherical forward end, said lug being provided with a reduced forward extension 142 which projects through a loosely fitting hole 144 formed in the spring. At its lower edge, the spring is supported by a screw 146 which extends through a loosely fitting hole 148 formed in the spring and is threaded in a boss 150 formed in tank wall 6. Said spring bears rearwardly against a hemispherical nut 152 fixed on said screw. Since cranks 136 engage the spring adjacent its lower edge, it will'be seen that advancing screw 146 inwardly or outwardly in boss 150 will adjust the `forward pressure of the spring on the cranks, thereby adjusting the pressure of cutter discs 68 against cutter roller 58, according to the character and texture of the paper being processed. Also, since the cranks engage the spring at equal distances from the vertical axis of the spring as defined by lug 140 and nut 152, and since the spring is free to tilt on said axis, said spring will function to equalize the pressure of the two cutter discs against the cutter roller; This eliminates unequal drag or resistance to the travel of the paper at its two edges, which might otherwise be caused by unequal cutter disc pressure.

In use, the operator first fiexes springs 52 outwardly to release arms 42 and 44, and pivots said arms upwardly and forwardly. This raises wall 74 away from the paste roller, and raises cutter roller 58 away from paste spreader 104 and cutter discs 68. Assuming that tank 2 has been partially filled with liquid paste, the operator A then lays a roll 32 of wall paper on arms 84 of slides 80, and leads paper 32' from said roll forwardly beneath roller 58 and over spreader 104 and cutter discs 68, then pivots arms 42 and 44 rearwardly and downwardly till they are re-engaged by springs 52. The paper roll 32 is then moved forwardly until it rests against both the paste roller 20 and wall 74, as shown in Fig. 4, first making sure that end guides 86 and 88 are spaced properly to receive the roll therebetween. Paste roller extensions 34 are then set to apply paste to all but the extreme edges of the paper, as shown in Fig. 5, and cutter slides 120 are adjusted to trim the desired amount from each edge ofthe paper. Fine adjustments of the cutter may be made by turning knurled nuts 134. Said nuts are also useful in making the small adjustments made necessary by the fact that from roll to roll of paper, the pattern placement on the paper, and hence the width of the edge portion to be trimmed away, may vary slightly.

The operator then grasps the upper end of paper 32' forwardly of cross bar 56, and pulls evenly thereon to pull paper from the machine, paste being applied to the paper by roller 20, and the edges of the paper being trimmed by cutter discs 68. When the desired length of paper has been pasted and trimmed, the operator simply pulls the paper rearwardly to sever it on cutting edge 72 of cross bar 56.

The principal features of this invention contributing to accurate (i.e. straight)` trimming of the paper edges reside in the support and guiding means for the wallpaper roll 32. It will be seen that said paper roll is carried in a substantially V-shaped trough, said trough being formed by wall 74 and the Aadjacent portion of paste roller, and that the spacing between said roller and the lower edge of said wall constitutes a slit" at the apex of the trough through which the paper 32' emerges. Since the paste roller is exactly parallel vto cutter roller V58, and since the paper contacts the paste roller as and immediately after it leaves the roll, it will be apparent that very accurate trimming of the paper will result if the paper is fed to the paste roller without lateral movement or wobble, and if there is sufficient friction` between the paper and the paste roller to ,prevent relative movement therebetween In "othe`words' thev paste roller should dominate the course Iof the paper.l

If the paper roll were mounted on any sort of`spindle or axle, and the spindle'or axle was not precisely centered at the geometric axis of the roll, or if the roll was even slightly mashed or deformed by handling, rotation thereof would cause an axial wobbling thereof about its true axis. Said wobbling of the roll would result in the fact that during portions of each revolution of the roll paper would tend to pay out faster from one end of the roll than from the other end. The resulting periodic 'lateral movement of the paper would cause a highly undesirable wavy or sinuous trimming by cut-y ters 68.

With the present centerless mounting of the paper roll, however, the body portion of the roll may wobble or gyrate as much as may be required without affecting the course of the paper. tact with the paste roller, and does not slip on the paste roller, the critical portion of paper, or that part contact-v ing the paste roller, will run straight and true.

' However, such wobbling of the paper roll will cause: uneven contact thereof, or a bumping action of the roll,. against wall 74 and against spring-loaded fingers 76. Such. action might cause uneven drag on the roll or even actual. bumps or shocks, which would tend to misalign the paperon the paste roller, were not special provisions made to prevent such occurrence. Any such misaligning action of.` fingers 76 is minor, since` said fingers are freely and inde pendently yieldable.

The provisions mentioned above tending to prevent misalignment of the paper on roller 20 by the action of wall.;

vide that the paste roller will truly dominate the course of the paper, are several in number. Firstly, the fact that roller 20 is freely rotatable and hence moves with the paper tends to prevent relative movement therebetween. It will thus be seen that the use of rol-ler 20 is important to accurate trimming, even if said roller did not perform the additional function of applying paste to the paper. Secondly, the use of'a roughened, anti-skid facing 30 on the paste roller, while wall 74 and fingers 76 are smooth and polished, provides additional friction between the roller and paper, while sliding movement of the roll on wall 74 and fingers 76 occurs relatively easily.` This favorable balance of friction, wherein the friction o f the paper against the paste roller greatly `overbalances the friction of the paper roll on any other member it contacts, is quite important. Thirdly, the above discussed favorable balance of friction is further enhanced by the fact that the paper contacts the paste roller over a wide area with consequently greater friction, as compared to the substantial line contact between the paper roll and fingers 76 or wall 74. Fourth, the pressure of springj to the roll which would prevent free rotation thereof.

Although not shown and not found to be essential for adequately accurate operation, a sixth feature experi-' mented with for reducing friction of the paper roll 'on` wall 74 and fingers 76 has been the insertion of small rollers or the like in the surfaces of said wall and said fingers and positioned to'engage the paper roll. Guides 86 and 88 could also be replaced by rollers on substantially vertical or canted axes, for the same purpose.

The device can be utilized as a paster only, with cutters 68 removed, or can be used as a trimmer only. lIn the latter case, tank 2 serves only as a frame in which the various working parts are mounted, and could be 0f any V suitable construction.

So long as it has uniform con-y ffr'v'wxfl ll"" "I 7 l' w' t 7 "While I have shown and described a specific embodiment of my invention, it will be apparent that many minor changes of structure and operation could be made without departing from the spirit of the invention as dened by the scope of the appended claims.

What I claim as new and desire to protect by Letters Patent is:

1. An improvement in a wallpaper trimming machine including a frame, a cylindrical cutter roller carried in said frame for rotation about its axis, and a cutter member carried by said frame and bearing against said eutter roller whereby to slit paper passing about said cutter roller, said improvement comprising a substantially V-shaped trough carried by said frame in parallel relation to said cutter roller and adapted to support a roll of paper laid longitudinally therein whereby paper led from said roll may be passed about said cutter roller, said trough having a longitudinal slit formed therein along the apex thereof, paper from said roll being drawn through said slit and passed about said cutter roller, said V-shaped trough constituting of a pair of angularly related Walls, the wall thereof contacted by said paper as it is drawn from said roll constituting the external surface of a guide roller mounted for rotation in said frame on an axis parallel to said trough and said cutter roller, said cutter roller being so positioned relative to said guide roller that said paper engages said guide roller around a substantial portion of the periphery thereof, the other wall of said trough being substantially planar` so as to have substantially only linear contact with said roll of paper, and a spring-loaded finger member carried movably by said frame and operable to urge said roll of papel' yieldably into said trough, said finger member being substantially planar so as to have substantially only linear contact with said roll of paper.

2. An improvement in a wallpaper trimming machine including a frame, a cylindrical cutter roller carried in said frame for rotation about its axis, and a cutter member carried by said frame and bearing against said cutter roller whereby to slit paper passing about said cutter roller, said improvement comprising a substantially V-shaped trough carried by said frame in parallel relation to said cutter roller and adapted to support a roll of paper laid longitudinally therein, whereby paper led from said roll may be passed about said cutter roller, said trough having a longitudinal slit formed therein along the apex thereof, paper from said roll being drawn through said slit and passed about said cutter roller, said V-shaped trough constituting a pair of angularly related walls, the wall thereof contacted by said paper as it is drawn from said roll constituting the external surface of a guide roller mounted for rotation in said frame on an axis parallel to said trough and said cutter roller, said guide roller being provided with a roughened anti-skid facing, the, other wall of said trough being relatively smooth and polished whereby to permit relatively easy sliding movement of said roll of paper thereagainst, and a spring-loaded finger carried movably by said frame and operable to urge said roll of paper into said trough, said finger member also being relatively smooth and polished as compared to said guide roller whereby to permit relatively easy sliding movement of said roll of paper thereagainst.

3. An improvement in a wallpaper trimming machine including a frame, a cylindrical cutter roller carried in said frame for rotation about its axis, and a cutter member carried by said frame and bearing against said cutter roller whereby to slit paper passing about said cutter roller, said improvement comprising a substantially V- shaped trough carried by said frame in parallel relation to said cutter roller and adapted to support a ro'il of paper laid longitudinally therein whereby paper led from said roll may be passed about said cutter roller, said trough having a longitudinal slit formed therein along the apex thereof, paper from said roll being drawn through said slit and passed about said cutter roller, said V-shaped trough constituting a pair of angularly related walls, the wall thereof contacted by said paper as it isi drawn from said roll constituting the external surface of a guide roller mounted for rotation in said frame on an axis parallel to said trough and said cutter roller, said guide roller being provided with a roughened anti-skid facing, the other wall of said trough being relatively smooth and polished and disposed at an obtuse angle to the immediately adjacent portion of the surface of the guide roller, and a spring-loaded finger member carried movably by said frame and operable to urge said roll of paper into said trough.

4. An improvement in a wallpaper trimming machine including a frame, a cylindrical cutter roller carried in said frame for rotation about its axis, and a cutter member carried by said frame and bearing against said cutter roller whereby to slit paper passing about said cutter roller, said improvement comprising a substantially V-shaped trough carried by said frame in parallel relation to said cutter roller and adapted to support a roll of paper laid longitudinally therein, whereby paper ledv from said roll may be passed about said cutter roller, said trough having a longitudinal slit formed therein along the apex thereof, paper from said roll being drawn through said slit and passed about said cutter roller, and a pair of end guides carried by said frame, and adapted to engage the ends of a roll of paper carried in said trough, one of said end guides being rigid whereby to index the paper roll with respect to the cutter member, and the other of said end guides being urged resiliently toward saidY rigid end guide to place said roll of paper under axial compression, whereby to slip the layers of paper in said roll over eac-h other to bring their edges into accurate registry.

5. An improvement in a wallpaper trimming machine including a frame, a cylindrical cutter roller carried in said frame for rotation about its axis, and a cutter mem- -ber carried by said frame and bearing against said cutter roller whereby to slit paper passing about said cutter roller, said improvement comprising a substantially V-shaped trough carried by said frame in parallel rela-y tion to said cutter roller and adapted to support a roll of paper laid longitudinally therein, whereby paper led from said roll may be passed about said cutter roller, said trough having a longitudinal slit formed therein along the apex thereof, paper from said roll being drawn through said slit and passed about said cutter roller, and a pair of end guides carried by said frame, and adapted to engage the ends of a roll of paper carried iu said trough, one of said end guides being rigid whereby to index the paper roll with respect to the cutter member, and the other of said end guides being urged resiliently toward said rigid end guide to place said roll of paper under axial compression, whereby to slip the layers of paper in said roll over each other to bring their edges mto accurate registry, said end guides being adjustable on sa1d frame longitudinally of said trough whereby to -accommodate the machine to receive rolls of paper of different widths.

References Cited in the tile of this patent UNITED STATES PATENTS 168,339 Miner Oct. 5, 1875 254,494 Miner Mar. 7, 1882 877,454 Randall 4 Jan. 21, 1908 1,239,960 Pohlman Sept. 1l, 1917 1,264,308 Kux Apr. 30, 1918 2,001,780 Fry May 2l, lQ'iJ' 2,204,934 Johnsen June 18, 1940 2,613,632 Renne Uct. 14, 1952 2,763,237 Harris Sept. 18, 1956 FOREIGN PATENTS 715,390 France Sept. 28, 1931` 

